I have just created a SAP note that relates with the steps to create a rollup in BWA. As you all may know
If new data packages (requests) are loaded into the InfoCube, they are not immediately available for Reporting via an aggregate/BWA index. To provide the aggregate/BWA index with the new data from the InfoCube, you must first load the data into the aggregate/BWA index tables/indexes at a time which you can set. This process is known as a Rollup.
Even though it mainly mentions BWA, most of it can also be applied to the creation of rollup to aggregates. Go ahead and check it out it contains documented screenshots with how to guides:
Please also check out the following links for guindace here too:
Also, for rollup issues involving BWA take a look at SAP note 1791621 – BWA Rollup/Change Run Issues
As for aggregates rollup issues, my best suggestion would be to recreate the aggregates, as per below:
Deactivate the aggregate with program SAP_AGGREGATES_DEACTIVATE, activate with the program
SAP_AGGREGATES_ACTIVATE_FILL then reactivate and fill with the RSDDK_AGGREGATE_DIRECT_FILL program.
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